Strap for Datejust 31 Rolesor Fluted Diamond / Oyster / Black Diamond

The Rolex Datejust 31 ref. 178313-0043v has a lug width of 16mm. This measurement should be taken with a digital calliper positioned internally between the two lugs, at the point of contact with the strap. This is a dimension specific to this case diameter and is not interchangeable with 17mm or 20mm straps from other variants within the Datejust family.

For a Rolesor case (stainless steel and 18k yellow gold), a square-scale alligator belly strap represents the most formal and coherent choice. A vegetable-tanned calfskin strap is preferable for daily wear, as it develops a personal patina over time. Shell cordovan, with its compact and luminous surface, is a refined alternative that holds its own against the polished gold lugs. Chromatically, warm tones work best: honey, champagne, tan leather, or burgundy.

Replacing the strap on a Datejust 31 requires a spring bar tool to remove the spring bars securing the strap to the lugs. It is advisable to use a tool with a teflon or nylon tip to avoid scratching the polished lugs. The operation can be performed independently with the correct tools or entrusted to a watchmaker. Standard 16mm spring bars are widely available; replacing them each time the strap is changed is recommended.

Yes, high-quality aftermarket straps compatible with the 16mm lug width of the Datejust 31 are available. On milanostraps.it, a curated selection of handcrafted straps is offered, produced with controlled manufacturing tolerances to ensure a precise fit to the lugs of reference 178313-0043v. Each strap is available in various lengths and materials, with bespoke customisation options through the Casati Milano atelier.

The lifespan of a leather strap depends on the material, care, and intensity of use. A quality alligator strap, with regular but not intensive wear, has an average lifespan of 2–4 years. Vegetable-tanned calfskin tends to last less if frequently exposed to perspiration and moisture, though it develops a distinctive patina. Shell cordovan is among the most durable and long-lasting leathers. All Casati Milano straps carry an 18-month warranty against manufacturing defects. It is advisable to avoid prolonged contact with water and to rotate between several straps to extend their useful life.